When did the current political division take off?

2017 was when we got so politically divided imo, what with the Charlottesville fiasco, the MeToo movement, Trump, Las Vegas... it all seemed to go rotten in 2017. Could make a case for 2016 too

The pump was primed back in the late 1970s/early 1980s with the merging of conservative Christianity and the Republican Party.  It's a terrible thing whenever a political party becomes one and the same with a specific religious belief.  The Reverand Jerry Falwell and Ronald Reagan are primarily responsible for that. However, back then most conservatives still believed in democracy and the constitution. Rhetoric began to escalate in the '90s when Newt Gincrich was speaker and again in the 2000s under George W. Bush. Yet, at that time conservative Christians still believed in winning via the electoral process and not overthrowing the government to impose their will. That all changed in 2015 with two things.

1) Obergefell vs Hodges legalized same-sex marriage in all 50 states.
2) Caitlyn Jenner comes out as a transwoman on the cover of Vanity Fair magazine and was congratulated by Obama.

Those two events are HUGE deals for social conservatives and represent a red line in the sand for them.  Since then, a "burn it all down" mentality has been metastasizing in this country until now, open calls for civil war and theocracy are becoming commonplace, even among elected officials.

This is going to come to a head one way or another and it's going to happen this decade. We're all going to have to buckle up.

It's hard to say.  A lot of that depends on how things play out between now and 2030.

Religion is the centerpiece of the division.  The media focuses on race and yes, that's an issue, but religion is the bigger deal.  Abortion and LGBTQ rights are the biggest issues.  Millennials and Gen Z are far less religious than baby boomers.  If America can hold together long enough for the boomers to age out of electoral majority, I think things will get better. But, that is a big IF, and with each passing day and week, I think that if gets less and less likely. 

I see one of the following things happening in the 2020s.

1) Balkanization of the USA via peaceful dissolution
2) Balkanization of the USA followed by open civil war
3) The former United States remains unified but is ruled with an iron fist, brutally, by a theocratic dictator.  It will be Trump at first but given his age, his reign won't be for very long.  My guess is that he'd pass the power to Donald Trump Jr. or Ivanka after he passes but who knows.
4) Donald Trump passes before 2024 and nobody else can hold together his base, so America survives by the skin of her teeth.

I'm hoping for #4.  #1 would be second best, but the problem with that is the cultural divide is more rural vs urban.  Plus, it's going to create a living nightmare for people in red states who don't fit the white heterosexual Christian patriarchal ideal.  I'm concerned that #2 or #3 are the most likely.

Hoping for 4!!!!

I know this is messed up but I don't see politics returning to normal until he kicks the bucket